The first aim of the project is to develop a critique of current methods of assessing overweight as a risk factor in epidemiological studies, and to define valid procedures for evaluating the performance of these methods. The second aim is to develop a model of body weight in a large population sample as a function of body composition, expressed in anthropometric and demographic variables. The third aim is to examine the relationships of (1) weight-height indices, (2) obesity and body composition, and (3) other aspects of physical configuration, to the risks of diabetes and of hypertension. The purpose is to ascertain what empirical effects the theoretical problems of indices have on risk estimates for two diseases believed to be associated with overweight, and to see if the aspects of body composition and configuration which affect risks of disease can be identified more accurately. An overall goal is to make specific recommendations for using anthropometric measurements (including weight and height) to assess risk factors in chronic disease in adults.